Anxiety is defined by Wiki as:

psychological and physiological state characterized bysomaticemotionalcognitive, and behavioral components.

[2] It is the displeasing feeling of fear and concern.[3] The root meaning of the word anxiety is ‘to vex or trouble‘; in either presence or absence of psychological stress, anxiety can create feelings of fear, worry, uneasiness, and dread.[4] Anxiety is considered to be a normal reaction to a stressor. It may help an individual to deal with a demanding situation by prompting them to cope with it. However, when anxiety becomes overwhelming, it may fall under the classification of an anxiety disorder.[5]

Anxiety is defined by the Cleveland Clinic Center for Continuing Education in the following way:

Anxiety is a natural response and a necessary warning adaptation in humans. Anxiety can become a pathologic disorder when it is excessive and uncontrollable, requires no specific external stimulus, and manifests with a wide range of physical and affective symptoms as well as changes in behavior and cognition. As outlined in the Diagnostic and Statistical Manual of Mental Disorders, fourth edition, text revision (DSM IV-TR), anxiety disorders include generalized anxiety disorder (GAD), social anxiety disorder (also known as social phobia), specific phobia, panic disorder with and without agoraphobia, obsessive-compulsive disorder (OCD), posttraumatic stress disorder (PTSD), anxiety secondary to medical condition, acute stress disorder (ASD), and substance-induced anxiety disorder.

Anxiety defined by Liz O’Donnell is: 
The measure of distress experienced in the distance between how we say we feel and think about something and what we decide to do and can and then actually do about it. Look at the following diagram:

Thought/feeling—————————(distress distance)——————————Action 

                                                               Thought/feeling—-Action        

Human beings are always in search of some form of homeostasis –   http://dictionary.reference.com/browse/homeostasis  without which we are placed under increasing amounts of stress. Reducing the distance, or bringing the thought/feeling in closer synchrony with the action we take to address the thought/feeling, is how we get closer to emotional and psychological homeostasis. For example – if you say you hate your job and then keep going everyday you have guaranteed an increase in the distress distance. Shortening the distress distance decreases the experience of anxiety. So if you hate your job and you must go everyday because you need the money then you will have to find another way of  describing your experience that is a true reflection of what is happening: e.g.This is not the best job for me yet it keeps me afloat – so I will do the best I can until I can change to something else.

This is not the same as putting a positive spin on a negative situation – it is an honest evaluation of a circumstance that you want to work toward changing. Anxiety is often accompanied by a sense of hopelessness that things cannot be different and hopelessness begets more anxiety. If you are trying to achieve something and you tell yourself it won’t work out for you – you have created your own distress distance – preparing for failure in my experience doesn’t help to mitigate the impact of not getting what you want – why would we invest time and energy toward something important and make a commitment to be on the wrong side of the outcome equation?

Becoming familiar with the ways in which we participate in both creating our own stress and distress is critical to discovering what we can do about it. See the following link for an explanation of the stress response:  http://www.wisc-online.com/objects/ViewObject.aspx?ID=AP13804           

So, keep a picture of the above diagram in your head – when you begin to feel anxious – and you will need to identify how and where this is experienced for you in your body – ask yourself how and where you are creating distress distance and what you can do in the immediate moment to reduce it?